Numerous women suffer from Stress Urinary Incontinence (SUI), caused by childbirth, loss of pelvic muscle tone, intrinsic sphincter deficiency (ISD) and/or estrogen loss. SUI and ISD lead to inadvertent loss of urine due to activities such as laughing, coughing, sneezing or exercising. Various treatments and appliances have been proposed to address this problem, including methods and apparatus to create pressure on the sphincter, such as implantable balloon devices. This type of surgery is traumatic and sometimes results in damage to the nerves around the bladder neck attributable to the magnitude of dissection required. Further, implantable balloons tend to erode tissue with which they are in contact. Bulking agents that are injected into the layers of the urethra have also been used, however, these agents usually dissipate over time, in some cases migrate to other parts of the body away from the site of implantation, and the problem eventually returns.
Surgical tape for supporting the female urethra to treat urinary incontinence has been successfully employed. For example, U.S. Pat. No. 6,273,852 discloses methods and apparatus for implanting surgical tape for supporting the urethra to address incontinence. U.S. Pat. No. 6,273,852 is owned by the present assignee and is incorporated herein by reference. Surgical tape and implantation systems for treating SUI are also available commercially from the assignee herein, e.g., under the trademark TVT™ tension free support for incontinence, sold by GYNECARE WORLDWIDE, a division of the present assignee.
In the use of a simple band of tape placed under the urethra, the action of treatment is the providing of a backstop to the urethra, over which the urethra will bend or against which it will compress. This treatment primarily addresses a condition known as hypermobility in stress urinary incontinence. This action essentially decreases the internal diameter of the urethra, thereby requiring a higher pressure within the bladder to overcome the closure mechanism of the urethra. To some degree, the intrinsic weakness of the urethral sphincter is enhanced by the placement of this type tape sling as well. However, there are many patients in which this treatment is not significantly effective to correct ISD. This is true particularly in women with severe ISD, in which the sphincter is significantly weakened and hypermobility is not present or mildly present. Severe ISD is diagnosed by urodynamic measurements of the opening or closing pressure of the urethra. In normal female patients, this pressure is approximately 60 cm of H2O to 120 cm of H2O. In a female patient who has a urethral sphincter dysfunction, it can be as low as 20 cm of H2O and the patient can still maintain some normal urine retention. In the worst cases, ISD in patients can be diagnosed by urethral closing pressures below 20 cm H2O. Notwithstanding known apparatus and techniques, alternative apparatus and methods are always of interest to provide results different from those of known methods, which, in certain instances and applications, may be preferable to known methods.